COLLABORATIVE EXPERIMENTS BY AKEBONO SATELLITE, TROMSO IONOSPHERIC HEATER, AND EUROPEAN INCOHERENT-SCATTER RADAR

Joint experiments using the Akebono satellite and the ionospheric heating facility and European incoherent scatter radar near Tromso were carried out iii November 1990 and February 1991. In these experiments, Tromso HF transmissions were amplitude modulated at frequencies of 2.5 and 4.0 kHz. Signals radiated from the polar electrojet (PEJ) antenna in the heated ionosphere at these VLF frequencies were detected for five passes out of seven passes of the semipolar orbiting Akebono satellite. A ground-based observation of the VLF radiation from the PEJ was made iii the November campaign at Lycksele iii Sweden, 554 km south of the heating facility. Measurements of electron density profiles and dc electric fields in the ionosphere were carried out by the EISCAT incoherent scatter radar [Folkestad et al., 1983] located iii the vicinity of the ionospheric heater. The results of the experiments axe compared with those obtained by ray tracing and full-wave analyses.